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131.
The key enzymes involved in modification of the steroid nucleus of sterol-transforming mycobacteria--3beta-hydroxysteroid oxidase (3-OH-SO, EC 1.13.1.2) and 17beta-hydroxysteroid dehydrogenase (17-OH-SDH, EC 1.1.1)--were isolated and characterized. It is shown that 3-OH-SO is a multifunctional enzyme catalyzing oxidation of the 3beta-OH group, delta5 --> delta4 isomerization, and 6-hydroxylation. Two forms of intracellular 17-OH-SDH that catalyze redox reactions at C17 were found, and their properties were determined. The presence of an extracellular 17-OH-SDH in Mycobacterium spp. (VKM Ac-1815 D and Et1) was demonstrated for the first time. 相似文献
132.
Timofeeva NM Gordova LA Egorova VV Nikitina AA Iezuitova NN 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2002,88(8):1028-1035
It has been found for the first time that protein deficit in female's nutrition during prenatal development of the offspring is accompanied by considerable changes in the activity of intestinal digestive enzymes and of the same hydrolases in the colon, liver and kidneys both in early and in late ontogenesis. It seems possible that changes of the small intestine enzyme functions and hydrolytic functions of other digestive and non-digestive organs in result of an unfavorable early "metabolic/nutritional programming" may be crucial in disorders of metabolic processes leading to development of diseases of risk in adult life. 相似文献
133.
134.
Kinetics of the dark relaxation of variable chlorophyll fluorescence, Fv, were studied after brief illumination of dark-adapted
barley leaves in order to understand the rapid reversibility of pulse-induced fluorescence increases, which is observed even
when fast linear electron transport to an external electron acceptor is not possible. Four kinetically distinct components
were observed which reveal complexity in the oxidation of the reduced primary quinone acceptor of Photosystem II, QA
−: the slowest component accounted for 4–5% of maximal Fv and had a life-time of several seconds. It is suggested to represent
a minor population of inactive Photosystem II centers. The other three components displayed first-order kinetics with half-time
of 6–8 ms (`fast' component), 60–80 ms (`middle' component) and 650–680 ms (`slow' component). The fast component dominated
Fv when methyl viologen or far-red light accelerated oxidation of plastohydroquinone. It shows rapid oxidation of QA
− during electron flow to plastoquinone commensurate with maximum linear electron flow through the electron transport chain.
The other two components were observed under conditions of restricted electron flow and excessive reduction of electron carriers.
Unexpectedly, the slow component, which is interpreted to reflect the recombination between QA
− and an intermediate on the oxidizing side of Photosystem II, saturated already at low irradiances of actinic light when plastoquinone
was not yet strongly reduced suggesting that dark-adaptation of leaves results not only in the loss of activity of light-regulated
enzymes of the carbon cycle but affects also electron flow from QA
− to plastoquinone. KCN poisoning or high temperature treatment of leaves produced a nonexponential pattern of slow Fv relaxation.
This effect was largely (heat treatment) or even completely (KCN) abolished by far-red light.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
135.
Mariia Bogacheva Anna Egorova Anna Slita Marianna Maretina Vladislav Baranov Anton Kiselev 《Bioorganic & medicinal chemistry letters》2017,27(21):4781-4785
The major barriers for intracellular DNA transportation by cationic polymers are their toxicity, poor endosomal escape and inefficient nuclear uptake. Therefore, we designed novel modular peptide-based carriers modified with SV40 nuclear localization signal (NLS). Core peptide consists of arginine, histidine and cysteine residues for DNA condensation, endosomal escape promotion and interpeptide cross-linking, respectively. We investigated three polyplexes with different NLS content (10?mol%, 50?mol% and 90?mol% of SV40 NLS) as vectors for intranuclear DNA delivery. All carriers tested were able to condense DNA, to protect it from DNAase I and were not toxic to the cells. We observed that cell cycle arrest by hydroxyurea did not affect transfection efficacy of NLS-modified carriers which we confirmed using quantitative confocal microscopy analysis. Overall, peptide carrier modified with 90?mol% of SV40 NLS provided efficient transfection and nuclear uptake in non-dividing cells. Thus, incorporation of NLS into arginine-rich cross-linking peptides is an adequate approach to the development of efficient intranuclear gene delivery vehicles. 相似文献
136.
137.
L G Loginova G I Khraptsova T I Bogdanova L A Egorova L M Seregina 《Mikrobiologiia》1978,47(3):561-562
A non-sporeforming gram-negative bacterium isolated from soils of Africa was shown to belong to the species Thermus ruber in its morphologo-cytological and physiologobiochemical properties. It differed from the Thermus ruber species described elsewhere (Loginova et al., 1975; Loginova and Egorova, 1975) only on colour: the former contained a bright-red pigment while the latter produced bright-orange pigments. 相似文献
138.
139.
N N Brustovetski? Z G Amerkhanov M V Egorova E N Mokhova V P Skulachev 《Biokhimii?a (Moscow, Russia)》1991,56(5):947-953
The parameters of energy coupling of mitochondria isolated from the livers of hibernating and awakening gophers were studied. The ATP/ADP-antiporter inhibitor carboxyatractylate slowed down the respiration rate, increased delta psi and decreased the ionic conductivity of the inner mitochondrial membrane as measured by the rate of the delta psi decline after addition of cyanide (in the presence of oligomycin and EGTA). A similar effect was produced by BSA, carboxyatractylate being fairly ineffective in the presence of BSA. In hibernating gophers the maximal rate of the uncoupled respiration and the ionic conductivity of the inner mitochondrial membrane were markedly decreased as compared with awakening gophers. The data obtained suggest that in awakening animals fatty acids induce the uncoupling of oxidative phosphorylation by the ATP/ADP-antiporter, this process being simultaneous with the activation of the respiratory chain. 相似文献
140.